Thomas, 29, moved to Bristol from Gloucester in the identical yr and has performed 108 video games for the club.
“We have all the time talked about bringing a core group via as we progress,” stated director of rugby Pat Lam.
Full-back Piers O’Conor, who like Thomas has made greater than 100 appearances, and Fijian wing Siva Naulago – who switched codes to union from Hull FC in 2020 – have additionally prolonged their stays with the club.
And the listing additionally contains Jake Heenan, Harry Thacker, Bryan Byrne, Jake Kerr, Max Lahiff, Jake Armstrong, Yann Thomas, plus academy graduates John Hawkins, James Dun, Will Capon, Sam Jeffries and Charlie Powell.
“We’re happy to see a proficient and skilled group of men decide to the Bears, nearly all of whom have been with us because the starting of our journey,” added Lam.
“That world class expertise is mixed with homegrown expertise who’re making the step up – we have seen that in the best way that the younger gamers have made their mark through the present marketing campaign.”
The Bears are at present tenth within the Premiership desk and are at residence to Exeter Chiefs on Friday.
Their remaining sport of the season can be away to Sale Sharks on 4 June.